Humming Sound: Normal?

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MyCarHasAbs

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Never kegged before up until today. Watched several YouTube vids on how to operate the tank properly. Seemed to work just fine when I was cleaning the keg. Hooked it up after transferring my German pils to the tank and it's sitting in my fridge.

There's a light humming sound, not a hissing sound but a hum. Is this normal? It's at about 11-12 PSI.
 
Make sure to open (or close) the CO2 tank valve all the way, never leave it in between, as it may not seal perfectly and leak.

The humming sound is probably the regulator, it hums or groans as it delivers the CO2. But... that sound should stop after a while when the pressure in the keg is equal to your regulator's setting, and no more gas is released. Then as CO2 is absorbed slowly, the regulator will let more gas in, but there will be quite a few minutes or even an hour in between. It's usually such a small amount, it goes through silently.

If it keeps humming, it's still releasing a significant amount of gas, which means you have a leak somewhere. Probably one of the fittings or the keg.
 
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Opened all the way. Tough to tell if what I'm hearing is the motor of the fridge or something else but all seems to be okay.
 
Put your ear next to the regulator, then turn the pressure up a bit, say 5-10 psi. If that's the sound you hear, and it doesn't stop, there's a leak somewhere.
 
fwiw, as well as the actual regulator, I've found the spring-loaded ball style of check-valve typically integrated within shut-offs can hum.
One of the so-equipped shut-offs on my 6-way manifold loves to sing (but it only knows the one tune...)

Cheers!
 
Tried to upload a video with audio but the dial isn't shaking anymore but if I put my ear right up to the dial I can certainly hear a very light hum. Not loud but it's there.
 
Unless you're using a high-pressure burst-carb technique, on a freshly filled keg the humming should stop within a couple of minutes - once the head space reaches equilibrium.

At "set and forget" pressures the beer can't accept gas through the beer/CO2 boundary fast enough to rattle the reg or a check-valve ball. Even with the burst carb I'd be surprised if the humming could persist for very long.

So if it keeps it up for much longer I'd be looking for a leak...

Cheers!
 
So in theory I should be able to put my ear up to the regulator and hear absolutely nothing... pure silence?

EDIT: if I move my ear about 6 inches away from the regulator, I hear nothing. If my ear is right on top 'touching' the regulator I hear a faint hum.
 
I just put two freshly filled cornies on 12psi in my conditioning fridge an hour ago.
Even using my stethoscope on the reg and manifold and keg lids I hear nothing...other than my wife clucking that I've lost my mind...

Cheers! ;)
 
Turns out I did have a very small leak. I opened the chest top and immediately heat a small hiss and a very unique odor. I leaned in closer to hear the hiss and it was coming from the gas post. I tightened the nut and suddenly I heard pure silence. Same with the regulator. Now hardly even hear a hum when my ear is next to it.
 
As soon as I tightened, the hiss stopped and the regulator made zero noise. It was a very "ohhh, that's silence" moment haha.
 
Glad you found the leak!

Those posts should be down pretty tight onto those stubs. The o-ring under the dip tube's flange makes the seal, so make sure they are in good condition. Use keg lube.
 
fwiw, as well as the actual regulator, I've found the spring-loaded ball style of check-valve typically integrated within shut-offs can hum.
One of the so-equipped shut-offs on my 6-way manifold loves to sing (but it only knows the one tune...)

Cheers!

The check valve is a little rubber duck bill inside the shut off valve assembly. It tends to vibrate when gas goes through the right way.
 
Duck bill?

None of my shut-offs use that style, they're all spring-loaded balls...

Cheers!

So are mine, maybe the balls flutter? I did notice that using 2 of those in series can create problems.

Some of the shutoffs use duck bills though...
 
So are mine, maybe the balls flutter? I did notice that using 2 of those in series can create problems.

Some of the shutoffs use duck bills though...

I have no doubt that one manifold check valve ball is rattling in the bore, not much more to the design to account for.

I've read each of this style check adds .5 psi resistance to gas flow. Not sure I believe that, but...

Cheers!
 

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